About The ImageHalley'sComet has
been know since at least 240 BC and possibly since 1059 BC. Its most
famous appearance was in 1066 AD when it was seen right before the
Battle of Hastings. It was named after Edmund Halley, who calculated
its orbit. He determined that the comets seen in 1531 and 1607 were
the same object that followed a 76-year orbit. Unfortunately, Halley
died in 1742, never living to see his prediction come true when the
comet returned on Christmas Eve 1758.

This image of Halley's Comets was taken during its 1986 appearance.
False-color digital enhancement was used to permit measurement of
slight brightness differences. (Copyright Calvin J. Hamilton)